Ring-Closing Metathesis and Nanoparticle Formation Based on Diallyldithiocarbamate Complexes of Gold(I): Synthetic, Structural, and Computational Studies
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- 作者：Saira Naeem ; Stefano A. Serapian ; Anita Toscani ; Andrew J. P. White ; Graeme Hogarth ; James D. E. T. Wilton-Ely
- 刊名：Inorganic Chemistry
- 出版年：2014
- 出版时间：March 3, 2014
- 年：2014
- 卷：53
- 期：5
- 页码：2404-2416
- 全文大小：564K
- 年卷期：v.53,no.5(March 3, 2014)
- ISSN：1520-510X
文摘
The gold(I) complexes [Au{S2CN(CH2CH鈺怌H2)2}(L)] [L = PPh3, PCy3, PMe3, CNtBu, IDip] are prepared from KS2CN(CH2CH鈺怌H2)2 and [(L)AuCl]. The compounds [L2(AuCl)2] (L2 = dppa, dppf) yield [(L2){AuS2CN(CH2CH鈺怌H2)2}2], while the cyclic complex [(dppm){Au2S2CN(CH2CH鈺怌H2)2}]OTf is obtained from [dppm(AuCl)2] and AgOTf followed by KS2CN(CH2CH鈺怌H2)2. The compound [Au2{S2CN(CH2CH鈺怌H2)2}2] is prepared from [(tht)AuCl] (tht = tetrahydrothiophene) and the diallyldithiocarbamate ligand. This product ring-closes with [Ru(鈺怌HPh)Cl2(SIMes)(PCy3)] to yield [Au2(S2CNC4H6)2], whereas ring-closing of [Au{S2CN(CH2CH鈺怌H2)2}(PR3)] fails. Warming [Au2{S2CN(CH2CH鈺怌H2)2}2] results in formation of gold nanoparticles with diallydithiocarbamate surface units, while heating [Au2(S2CNC4H6)2] with NaBH4 results in nanoparticles with 3-pyrroline dithiocarbamate surface units. Larger nanoparticles with the same surface units are prepared by citrate reduction of HAuCl4 followed by addition of the dithiocarbamate. The diallydithiocarbamate-functionalized nanoparticles undergo ring-closing metathesis using [Ru(鈺怌HC6H4OiPr-2)Cl2(SIMes)]. The interaction between the dithiocarbamate units and the gold surface is explored using computational methods to reveal no need for a countercation. Preliminary calculations indicate that the Au鈥揝 interactions are substantially different from those established in theoretical and experimental studies on thiolate-coated nanoparticles. Structural studies are reported for [Au{S2CN(CH2CH鈺怌H2)2}(PPh3)] and [Au2{S2CN(CH2CH鈺怌H2)2}2]. In the latter, exceptionally short intermolecular aurophilic interactions are observed.